An inflammatory marker for predicting prostate cancer in prostate biopsy: monocyte-to-lymphocyte ratio

Objective: To evaluate the predictive role of the inflammatory parameters, especially monocyte-to-lymphocyte (MLR) ratio, on the diagnosis of prostate cancer (PCa). Material and Methods: The data of patients undergoing prostate biopsy between July 2015 and July 2019 were retrospectively analyzed. The data including age, PSA, neutrophil-to-lymphocyte (NLR), platelet-to-lymphocyte (PLR), MLR and histopathologies were recorded. Patients were grouped as benign prostatic hyperplasia (BPH), PCa and prostatitis according to PBx histopathology and all variables were analyzed. Results: Pathology results of 338 patients are as follows: 124 (36.7%) BPH, 132 (39.1%) PCa and 82 (24.3%) prostatitis. Patients with PCa were older and had higher serum PSA, PLR, NLR and MLR values compared to non-PCa patients. In the comparison made by excluding metastatic patients, only serum PSA and MLR values remained statistically high. All three parameters had significant AUC to predict PCa in entire-cohort, but only the MLR had significant AUC to predict PCa in the cohort which metastatic patients were excluded. Multivariate logistic regression analysis revealed that only serum PSA and MLR values were significant independent predictors of PCa. Conclusion: In our study, it was observed that only MLR among all inflammatory markers found to be high in PCa patients continued to be high in nonmetastatic PCa patients. In the multivariate regression model created from age, PSA and MLR, MLR was found to be a significant independent predictor of PCa like PSA. MLR can be used as an inexpensive, easily accessible and applicable new marker to predict PCa. Keywords: inflammatory markers, monocyte-to-lymphocyte ratio, prostate biopsy, prostate cancer